If its a magnum its loaded with a mag primer in this house. Out of the mag primers ive probably had my best luck with Fed match mags for grouping. I also use alot of standard 215m and cci mag. both are quite a bit hotter primer then the ww primers.

Any time you get up near 70gr of powder it's a good idea to use a magnum primer, especially with slow powders like H1000. Of course not all primers are created equal so if you get a complete and smooth burn using a Win WLR primer then that's what you should use. (but I would test all the magnum primers I could find first)

My go to primer for my 300WM's, or any load over 60 gr of powder has been Fed215M's, but I have yet to see any difference in ES, velocity, or cold temperature performance compared to the "non-match" 215's. My current load is 210 Berger VLD/LRAB's, with 79gr Retumbo, Norma brass,Fed215M/215, 2904FPS, ES 10FPS, .25-.5MOA.